{"id":14734,"date":"2026-09-14T06:13:10","date_gmt":"2026-09-14T06:13:10","guid":{"rendered":"https:\/\/bonitopak.com\/?p=14734"},"modified":"2026-09-19T06:38:19","modified_gmt":"2026-09-19T06:38:19","slug":"how-are-pulp-egg-trays-made","status":"publish","type":"post","link":"https:\/\/bonitopak.com\/de\/how-are-pulp-egg-trays-made\/","title":{"rendered":"How Are Pulp Egg Trays Made? From Recycled Paper to Finished Tray"},"content":{"rendered":"

Von Leo Chan<\/strong>\u00a0 | Autor, BonitoPak | \u00dcber 20 Jahre Erfahrung im Bereich Verpackungen aus Formzellstoff<\/p>\n

Pulp egg trays are made from two ingredients: paper and water. Recycled paper is broken down into a fiber slurry, vacuum-formed on a mesh mold shaped like the tray, and then dried until it holds its shape. That’s the whole recipe.<\/span><\/p>\n

Search “how are pulp egg trays made” and you get that three-word answer: pulping, forming, drying. The details are where trays start to differ from each other. Fiber quality, forming time, drying method, and finishing all shape how stiff the tray feels, how well it stacks, and whether it protects eggs on a rough road. This article follows the material through the line and points out what each stage means for the tray that lands on your packing table.<\/span><\/p>\n

The Short Version<\/strong><\/h2>\n

The egg tray manufacturing process runs in six stages.<\/span><\/p>\n\n\n\n\n\n\n\n\n\n
B\u00fchne<\/span><\/td>\nWhat happens<\/span><\/td>\nWhat it controls<\/span><\/td>\n<\/tr>\n
1. Sorting<\/span><\/td>\nRecycled paper is collected, sorted, and cleaned<\/span><\/td>\nFiber quality and color<\/span><\/td>\n<\/tr>\n
2. Pulping<\/span><\/td>\nPaper is beaten with water into a slurry<\/span><\/td>\nConsistency and strength<\/span><\/td>\n<\/tr>\n
3. Forming<\/span><\/td>\nVacuum pulls fiber onto a mesh mold<\/span><\/td>\nShape, wall thickness, cell geometry<\/span><\/td>\n<\/tr>\n
4. Drying<\/span><\/td>\nWater is driven out with heat or air<\/span><\/td>\nRigidity and dimensional stability<\/span><\/td>\n<\/tr>\n
5. Finishing<\/span><\/td>\nHot pressing, trimming, and inspection<\/span><\/td>\nSurface, edges, and consistency<\/span><\/td>\n<\/tr>\n
6. Packing<\/span><\/td>\nTrays are nested, counted, and palletized<\/span><\/td>\nFreight efficiency<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Stage 1: Collecting and Sorting the Raw Material<\/strong><\/h2>\n

Most recycled paper egg trays in the US market start as newsprint, cardboard, and office waste. Used egg trays go back in too, which is one reason this product recycles so cleanly into itself.<\/span><\/p>\n

Not all waste paper is equal. Clean, dry paper with long fibers makes stronger trays. Paper contaminated with plastic film, wax coatings, or heavy adhesives causes problems that show up later as weak spots or specks in the finished tray. Sorting is unglamorous work, but it sets the ceiling for everything downstream.<\/span><\/p>\n

Some producers use plant fiber instead of recycled paper. Sugarcane bagasse and bamboo are the common choices, and both behave like virgin fiber, which gives a lighter color and a cleaner surface. BonitoPak runs recycled paper, bagasse, and bamboo, and you can see the options on our<\/span> materials page<\/span><\/a>.<\/span><\/p>\n

Stage 2: Pulping the Fiber<\/strong><\/h2>\n

Sorted paper goes into a hydrapulper, which is essentially a large tank with an agitator. Paper and water are beaten together until the sheets break apart and the fibers separate. Equipment makers typically describe a paper-to-water ratio in the area of 1 to 3, with roughly 40 minutes of high-concentration stirring before the slurry moves on.<\/span><\/p>\n

The slurry is then screened. Screening pulls out staples, sand, plastic scraps, and anything else that survived sorting. After that the pulp is diluted to the consistency the forming machine needs, because thin slurry and thick slurry produce very different wall thicknesses at the same forming time.<\/span><\/p>\n

Additives can enter here. Pigment for colored trays goes into the pulp system rather than onto the surface. Water-resistance additives are also added at this stage when a job calls for them. For plain<\/span> recycled paper egg trays<\/span><\/a>, there’s usually nothing in the mix but fiber and water.<\/span><\/p>\n

Stage 3: Forming the Tray<\/strong><\/h2>\n

This is where a pool of gray slurry becomes something egg-shaped.<\/span><\/p>\n

The forming mold is a metal tool covered in fine mesh, cut in the exact shape of the tray. It dips into the slurry while a vacuum pump draws water through the mesh from the inside. Fiber collects on the mesh surface in an even layer, and the tray takes shape in seconds.<\/span><\/p>\n

Three things decide how thick that layer gets:<\/span><\/p>\n